Moreta, dragonlady of Pern

All seems well on Pern until a mysterious ailment strikes killing myriads of holders, craftsmen, and dragonriders. Pern is left in mortal danger with noone to rise to char the prarasitic Thread. The dragonriders of Pern are in danger from a mutated strain of influenza. The dragonriders of Pern are in danger from a mutated strain of influenza.